1. Field of the Invention
The present invention relates to a process for the setting of an electronic digital display for a desired time period, in particular the cooking time of a microwave oven, in which the setting is undertaken through a series of stepping pulses. Furthermore, the invention relates to a circuit for the implementation of the process.
2. Discussion of the Prior Art
German Patent Application No. P26 28 794.5 describes an electro-mechanical setting arrangement for an electronic digital display. Through the intermediary of an impulse generator which must be manually actuated, there are generated stepping pulses for the setting of the electronic digital display. Herein, the input speed is quite restricted. Accordingly, for this purpose there has been proposed in German Patent Application No. P27 26 383 to superproportionately increase the frequency of the stepping pulses from a predetermined input frequency. This display can thus be rapidly adjusted over a number of hours.
In German Patent Application P28 28 285.1 there is proposed a process for the generation and processing of stepping pulses for the setting and, respectively, correcting of an electronic digital display. Hereby, a microprocessor is connected intermediate the electromechanical impulse generator and the display. This arrangement results in an increase in the potential input speed.
When it should become possible to set hours and minutes, then the microprocessor for effecting the setting has to process 24.times.60=1440 setting possibilities.
In arrangements which there is to be set a desired time period for an operating sequence, for example such as ovens, particularly microwave ovens, it is not of particular significance that within the entire possible time range the desired time period is accurately set to the last place. Thus, for example, in microwave ovens at short desired time periods it is necessary to provide a setting capability which is accurate to within seconds. For lengthier desired time periods it is sufficient to have a setting which is accurate to within minutes.